/*
 * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008)
 * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice including the dates of first publication and
 * either this permission notice or a reference to
 * http://oss.sgi.com/projects/FreeB/
 * shall be included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
 * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 * Except as contained in this notice, the name of Silicon Graphics, Inc.
 * shall not be used in advertising or otherwise to promote the sale, use or
 * other dealings in this Software without prior written authorization from
 * Silicon Graphics, Inc.
 */
/*
 *
 * OpenGL ES 1.0 CM port of GLU by Mike Gorchak <mike@malva.ua>
*/

#ifndef __glubackend_h_
#define __glubackend_h_

#include "trimvertex.h"
#include "gridvertex.h"
#include "gridtrimvertex.h"

class BasicCurveEvaluator;
class BasicSurfaceEvaluator;

class Backend
{
   private:
      BasicCurveEvaluator&   curveEvaluator;
      BasicSurfaceEvaluator& surfaceEvaluator;

   public:
      Backend(BasicCurveEvaluator& c, BasicSurfaceEvaluator& e):
              curveEvaluator(c), surfaceEvaluator(e) { }

      /* surface backend routines */
      void bgnsurf(int, int, long);
      void patch(REAL, REAL, REAL, REAL);
      void surfpts(long, REAL*, long, long, int, int, REAL, REAL, REAL, REAL);
      void surfbbox(long, REAL*, REAL*);
      void surfgrid(REAL, REAL, long, REAL, REAL, long);
      void surfmesh(long, long, long, long);
      void bgntmesh(const char*);
      void endtmesh(void);
      void swaptmesh(void);
      void tmeshvert(GridTrimVertex*);
      void tmeshvert(TrimVertex*, REAL*, REAL*);
      void tmeshvert(GridVertex*);
      void tmeshvert(REAL u, REAL v, REAL*, REAL*);
      void linevert(TrimVertex*, REAL*, REAL*);
      void linevert(GridVertex*);
      void bgnoutline(void);
      void endoutline(void);
      void endsurf(void);
      void triangle(TrimVertex*, TrimVertex*, TrimVertex*);
      long get_output_style(void);

      void bgntfan();
      void endtfan();
      void bgnqstrip();
      void endqstrip();
      void evalUStrip(int n_upper, REAL v_upper, REAL* upper_val, int n_lower, REAL v_lower, REAL* lower_val);
      void evalVStrip(int n_left, REAL u_left, REAL* left_val, int n_right, REAL v_right, REAL* right_val);
      void tmeshvertNOGE(TrimVertex* t);
      void tmeshvertNOGE_BU(TrimVertex* t);
      void tmeshvertNOGE_BV(TrimVertex* t);
      void preEvaluateBU(REAL u);
      void preEvaluateBV(REAL v);

      /* curve backend routines */
      void bgncurv(void);
      void segment(REAL, REAL);
      void curvpts(long, REAL*, long, int, REAL, REAL);
      void curvgrid(REAL, REAL, long);
      void curvmesh(long, long);
      void curvpt(REAL);
      void bgnline(void);
      void endline(void);
      void endcurv(void);

   private:
      int  wireframetris;
      int  wireframequads;
      int  npts;
      REAL mesh[3][4];
      int  meshindex;
};

#endif /* __glubackend_h_ */
